1. Field of the Invention
The present invention relates to optical devices and optical apparatuses and more particularly relates to an optical device including an optical element chip in which an optical element for emitting or receiving light and an optical apparatus including the optical device.
2. Description of the Prior Art
Conventionally, optical apparatuses in which an optical element for emitting or receiving light is mounted have been known.
For example, in Japanese Laid-Open Publication No. 10-135397, as shown in FIG. 8, disclosed is a semiconductor device (optical apparatus) including a printed wiring board (wiring board) 501 including a concave portion 507 in a surface thereof, an interconnect metal 502 formed on part of the surface of the printed wiring board 501 excluding part of the substrate in which the concave portion 507 is formed, a resin portion 503 of a chip-on-board semiconductor device placed on a surface of the concave portion 507 of the printed wiring board 501 and including a plastic-sealed semiconductor element (optical element) mounting portion, an external lead 504, a connection portion 505 which is part of the external lead 504, is formed so as to be parallel to the surfaces of the printed wiring board 501 and is connected to the interconnect metal 502. In Japanese Laid-Open Publication No. 10-135397, it is described that in the semiconductor device, the resin portion 503 of the chip-on-board semiconductor device is accommodated in the concave portion 507 in the printed wiring board 501 and thus reduction in thickness of the semiconductor device can be achieved.
However, in the semiconductor device described in Japanese Laid-Open Publication No. 10-135397, the resin portion 503 of the chip-on-board semiconductor device is merely placed on the surface of the concave portion 507 of the printed wiring board 501. That is, a surface of the resin portion 503 of the chip-on-board semiconductor device is exposed. Thus, unnecessary light might enter into the semiconductor device from the outside of the semiconductor device. Herein, unnecessary light means light that the semiconductor device should not receive or light that the semiconductor device should not emit.
When the semiconductor element is an element for receiving light, such as a light receiving element, the resin portion 503 of the chip-on-board semiconductor device receives light. In the semiconductor device including the light receiving element, image analysis and the like are performed using light received by the semiconductor element in many cases. Therefore, if received light includes unnecessary light, the semiconductor device can not properly perform analysis such as image analysis or like problems arise.
When the semiconductor device is an element for emitting light, such as a light emitting element, unnecessary light is reflected at a surface of the semiconductor device and mixed with light emitted by the semiconductor element, so that the light is emitted to the outside of the semiconductor device. In the semiconductor device including the light emitting element, light emitted from the semiconductor element is used as a light source for data writing in many cases. Thus, if light emitted from the semiconductor element includes unnecessary light, desired light can not be obtained. Accordingly, data can not be correctly written in a storage medium and like problems arise.
As described above, when the semiconductor device is used for image analysis, desired light can not be received, and when the semiconductor device is used as a light source for data writing, desired light can not be emitted. Therefore, the semiconductor device can not be installed in a video camera, a digital camera, a digital still camera and the like, which require high analysis accuracy.
Moreover, in recent years, reduction in thickness for a video camera, a digital camera, a digital still camera and the like has been required. Accordingly, reduction in thickness for a semiconductor device to be installed in a video camera, a digital camera, a digital still camera and the like is desired.